Abstract
Using the enzyme acid phosphatase as a marker for lysosomes, a histochemical study has been made of the effects of the operative procedure for partial hepatectomy upon the lysosomes of rat liver. The procedure was considered in three stages: i) ether anaesthesia; ii) laparotomy; iii) laparotomy and handling of the left and ventral lobes. With increasing severity of procedure shorter times of incubation in test medium were required to demonstrate lysosomes in liver. This was considered to indicate an increased permeability of lysosomal membrane to the substrate, β-glycerophosphate. Response was not immediate, but increased to a maximum with time, finally returning to normal. The reversible change in lysosomes was considered to reflect a physiological response by these particles to cell damage.